What is a hydrosalpinx?

Hydrosalpinx, derived from Greek, literally means “water tube.” The fallopian tube is distended with fluid to a variable degree. If both tubes are distended, they are called hydrosalpinges. It is a common type of tubal problem that causes infertility. Nearly half of all couples who suffer from infertility have a female-related cause. Of these women, more than half have a disease in the uterotubal complex (i.e., upper female reproductive tract), and approximately one-third of them have hydrosalpinges.

What causes a hydrosalpinx?

A hydrosalpinx is almost always a result of a past pelvic infection. The most common bacteria at fault are gonorrhea, chlamydia, staphylococcus, streptococcus and pelvic tuberculosis. Bacteria infect the upper reproductive tract causing destruction of the tubal wall, adhesions and abscesses. The end result after the infection has cleared is a dilated fallopian tube often shrouded with surrounding adhesions in the pelvis. The lateral end, or fimbria of the tube is usually agglutinated together essentially blocking the opening between the ovary and the tubal conduit which leads to the uterus. Because of the distal obstruction and poor tubal wall motion, it is thought that the uterotubal derived fluid, which normally drains out the end, becomes trapped and distends the tube.

How is one diagnosed?

The upper reproductive tract is best assessed by either radiographic imaging or surgery. Transvaginal ultrasound can often detect a hydrosalpinx, but the majority of them cannot be seen (sensitivity = 34%). The usual first line approach is an x-ray called an HSG—hysterosalpingogram (uterus/tube/picture). Opaque dye is instilled through the cervix with a catheter into the uterus and eventually the tubes. The test often causes uncomfortable cramps when the muscular uterus contracts. A hydrosalpinx is evident when the tube appears dilated and will not allow the dye to spill out into the peritoneal cavity. Occasionally, an HSG may incorrectly determine the presence (specificity = 83%) or absence (sensitivity = 65%) of a hydrosalpinx. For example, if the tube is blocked at the junction of the uterus and tube, then the dye will not enter the hydrosalpinx and it will not be seen. Accordingly, a more accurate way to assess the tube is by laparoscopy. Not only can a surgeon directly visualize a hydrosalpinx, but also evaluate the presence of other pelvic pathology.

What impact does it have on fertility?

Hydrosalpinges are blocked or severely compromised tubes which greatly impair fertility. The sperm cannot reach the egg for fertilization, the egg cannot be picked up by the tube and an embryo cannot travel back to the uterus for implantation. The only way for couples to get pregnant is to repair the tube or bypass it.

How is it treated?
Historically, hydrosalpinges were repaired surgically. Initially in the 1970’s, the surgeon would make a small abdominal incision to confirm the diagnosis, remove surrounding adhesions and open the distal end of the tube. At that time, the subsequent pregnancy rates were very poor (less than 15% / year) because post-operative adhesions would typically return. During the 1970 –80’s, microsurgical repair was encouraged to minimize the extent of post-operative adhesion formation. In the late 1980’s – early 1990’s, laparoscopy became the primary approach since even fewer adhesions would form. While surgical repairs can offer some hope, most patients continue to have very disappointing results. Opening an obstructed, dilated tube still leaves a patient with a damaged tube unable to pick-up the egg or move the embryo to the uterus.

If a hydrosalpinx is the obstacle to conception, then the most efficient and cost effective way to conceive is to bypass the obstruction. In vitro fertilization (IVF) takes the egg out of the body for fertilization by sperm in a Petri dish. After a few days, the embryo is gently transferred into the uterus. In effect, in vitro fertilization is nothing more than replacing the functions of the fallopian tube. It is the most effective way for a patient with a hydrosalpinx to get pregnant.

Recently, a considerable number of reports are describing the negative impact a hydrosalpinx has on the success rate of IVF. It has been shown that implantation rate is markedly reduced (about 50%), and the miscarriage rate is increased. These effects substantially reduced the pregnancy and take-home baby rates. Several studies have found that the fluid retained in the tube is embryotoxic and may impair the endometrium’s receptivity to allow the embryo to implant. Some suspect that the enlarged tube may compromise the blood flow to the ovary causing a poorer response to gonadotropins. Several studies have shown that removing the hydrosalpinx improves the subsequent success of IVF. It is now generally recommended to remove these tubes before one proceeds to IVF. Surgically removing the hydrosalpinx though is not without risk, so it is important to be properly evaluated to develop an appropriate treatment plan.